Conversion of hydrocarbon gases



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Apnl 18, 1933- G. EGLoFF CONVERSION OF HYDROCARBON GASES Filed April 8, 1951 Zcfc f77 6.55: @M

Patented pr. 18, 19.33`

'UNITED STATES PATENT- OFFICE GUsTAv EGLOIF, or CHICAGO, ILLINOIS,I AssIGNon To UNIVERSAL OIL raODUcTs ooMrANY, or CHICAGO, ILLINOIS, A CORPORATION or soUTH DAKOTA CONVERSION F HYDROCARBON GASES Application led April 8,

This invention relates to a process for the conversion of hydrocarbons, to produce lighter products therefrom, such as acetylene or similar gases and liquid motor fuels. More specifically, the invention relates to 4the conversion of hydrocarbon gases such as those produced'in an oil cracking process and others, said conversion belng influenced by the action of ultra violet light and resulting ing zone and wherein the reactions progress-A ing therein may be carried out in the presence of ultra violet rays, the lighter evolved vapors of reaction being therea ter subjected tov fractionation, condensationl and collection.

Other and further objects and advantages of the invention will become apparent from the following descriptionand accompanying diagrammatic drawing illustrating a 3o side-elevational view of one form of apparatus in which the invention may be carried out.

Referring to the drawing, raw oil charging stock for a cracking process may be introduced into the s stem from a line 1, controlled by valve 2, by a pump 3 dischar ing into a line 4, controlled by valve 5, lead' mg into the upper or fractionating ortion '16 of a combined fractionator an reaction' 40 chamber 6 wherein-'hydrocarbon vapors from a reaction zonev of such process are under.

going fractionation. The raw oil, in a' relatively cool state, passes countercurrent to the ascending vapors within said ractionator 16, serving to cool said vapors and condense the 'within saidhe'ating element may progress to 1931.l SlerilN'O. 528,530.

pump 9, which discharges into a line 10,

controlled by valve 11., Raw oil may, if desired, be passed directly into line 7 through line 4 and valve 5', passing thence to pump 9.

The reiiux condensate and raw oil chargpounds per square inch more or less.

After subjection to the desired conversion conditions within .heating element 12, the .heated products may be discharged from said heating element through a line 14, controlled by valve 15 and introduced into an enlarged reaction zone 16 preferably maintained under a substantial superatmospheric pressure which may be substantially the same or lower than the pressure maintained in the heatin element, and wherein the reactions starte the desired degree of completion, sufficienttime period for this purpose .being allotted to the products under treatment in chamber 16. The lighter vaporousl products of-rel action separate from the liquid portions 90 sok 'ing stock passing through said vline 10, may Y thereof, the latter being withdrawn from .said

reaction 'chamber through a' line 17, controlled by valve 17 to storage or elsewhere as desired or in case the reaction is allowed to progress to the stage where only coke or carbonaceous material remain as the residual product said coke or carbonaceous ma terial may collect within the chamber to be removed through manway 16 after operation of the process is completed.

The vaporous products of lreaction may be introduced into fractionating chamber 1,6

through a line 7 containing a valve 8 interposed between said fractionator and the reaction chamber, thus enabling the fraction- 'ator to be maintainedunder a reduced pressure, if desired. The vapors on entering said fractionator pass upwardly therethrough, countercurrent to the downwardly flowing raw oil and/or reflux condensate, as previously described, and after suiicient treat` ment within said fractionator, the lighter,

gasoline-likeportions ofthe vaporsmay be withdrawn therefrom from a suitable tray in said dephlegmator or fractionator through a line 18, controlled by valve 19, and passed from said line to suitable, cooling, condensing and collecting equipment of the system (not shown). In order to assist in controlling the boiling-point range' of the asoline- 'like fractions Aand the quality of t e gases 'produced in the process, and in order to further maintain a relatively constant temperature and control thereoverat the outlet of said fractionator, any desired cooling medium, such as pressure distillate from a receiver of the process may be introduced into the upper portion of said fractionator from a line 20, controlled by valve 21, by pump 22, discharging into aline 23 leading into a suitable spraying device (not shown) or any other distributing means disposed in the upper limits of said fractionator. In this manner, the valuable hydrocarbons constituting the gasoline fractions of the process may not be subjected to retreatment with the gaseous hydrocarbons produced in this stageor` the process. y

Hydrocarbon gases separated out in and evolved from fractionator 16 maybe Withdrawn from the top of said fractionator through a line 24, controlled by valve 25 and introduced through said line into a secondary` heating element 26 disposed Within a suitable-1 furnace 27 where they may be subject tothe desired retreatment of the process. Any desired temperature may be utilized within said secondary heating element 26, but preferably a temperature range of from 1200" F. to 1850 F. may be employed. Pressures utilized within said' secondary heating element 26 are preferably lower than those employed within the primary heating element 12, and

ma range from about 200 pounds per squarev inc to about 4[400 pounds persquare lnch,

depending upon the degree or yield of acety` lene or highly unsaturated hydrocarbons re .i

quired.

p Prior to the admission of the gases from the cracking unit to the succeeding secondary heating element 26, hydrocarbon gas mixtures from other s'ources may be admitted from a line 24 containing a valve 25 under pressures produ-ced if necessary by pumping means not shown. Gases introduced atthis point may be natural gases occurring in as-A sociation with crude petroleum or otherwise, gases from a distillation of crude'petroleums, gases produced in the distillation of coal or shale and from any other source. As the process of the invention is separate from any particular cracking process 1t comprises operation upon any ofthe gases mentioned arising from other sources than a cracking process and may be conducted upon any of thesev their period of reaction within said chamber j 30, the highly heated hydrocarbons are subjected. to the polymerizing action of a mercury llght or other source of ultra violet rays `3l within said chamber, leads 30 and 31 indicating electrical terminals for a lamp. Other means of subjecting the gases to the faction of ultra violet light may be employed; for example, the light may be admitted through quartz windows atditferent points in thechamber,the source of the rays being then outside the chamber. This portion of the system is largely responsible for the high yield of acetylene, which may be 40% or more of the gas collected in the receiving portion of thel system, and the pressure conditions employed therein to produce such acetylene or unsaturates of like nature is', as* hasfbeen i stated, preferably that corresponding to a high degree of vacuum, or'f" be substanmfy vtially atmospheric or only's ghtly sub-at- Afteiisubljection to the desired reaction and polymerizing action of the ultra violet ray llght on'fthe unsaturates under treatment within said reaction chamber 30, condensed liquids accumulating in the bottom of the treating chamber may be withdrawn through aline 32 containing a valve 33 and depending upon', the nature of these liquids they may be "utilized directly as motor or other fuel or returned to acracking zone for further conversion. When subatmospheric pressures are employed in the .Withdrawn from said ractionator through a line 35, controlled by-valve 36,byv a pump 55 discharging into a line 56 controlled by a valve 57 either to a conversion zone or to storage, (such a pump being necessary as in the case of pump 52 when subatmosphericpressures are employed in the system) either from the system, or returned for further treatment; while the lighter desired components from said fractionator 34 may be passed through a line 37, controlled by valve 38 into a condenser or cooler 39 wherein liquefaction and separation of gases is obtained. When vacuum is employed in the treater of the fractionator, more eiiicient cooling means may be employed around condenser coil 39 than are usually used in oil refineries, for example, instead ofwater at atmospheric temperature cold brines may be circulated or the coils cooled by expansion of low boiling gases such as carbon dioxide or sulfur dioxide. The cooled products then pass from said cooler through a line 40, controlled by valve 41 into a receiver 42, wherein the liquids and gases separate.V The incondensible gases from the system may be withdrawn from said receiver through a line 43, controlled by valve 44 through a vacuum pump 45, which discharges into a line 46 which may lead to storage or absorption equipment. When subatmospheric pressures are used it may be advisable to employ absorption equipment upon the vapors for the complete recovery yofgasoline fractions though such absorption equipment is not shown in the drawing. The liquid fractions separated out within said receiver 42 may be withdrawn therefrom through lva line 47, controlled by valve 48, (these containing large amounts of gasoline hydrocarbons of the aromatic series) and pumped by pump 49 into a lineV 50 controlled by a. valve 51 to any desired point.

While numerous examples of operations upon different hydrocarbon gases and re-V sults obtainable therefrom might be given, it will suiice to cite a case involving the use of cracked gases and one using natural gas, such cases being generally typical of the gases which may be employed, the cracked gases representing a class containing relatively large `amounts of unsaturated derivatives and being somewhat similar to the gases obtained from shale and coal distillation and the latter type being' similar to the gases obtained in the straight or non-cracking distillation of crude petroleums.

As one example, vthe gases produced by cracking a 30 gravity Mid-Continent gas oil Vat a pressure of 250 pounds per square inch an absolute pressure of about 5 pounds per square inch. Under these conditions and in the presence of a source of ultra violet of suiiicient intensity thereV may be produced an overall yield based on the gas oil charging stock of gasoline boiling range hydrocarbons, these gasoline hydrocarbons being of highly aromatic nature corresponding to a benzol equivalent of 75 to 80% whereas without the use of the secondary conversion step upon the xed gases the corresponding yield of gasoline may be only 65 to 7 0% with a benzol equivalent of 60%. The fixed gases constituting the nal gaseous end product of the gas treating process such as leave the absorption plant as gases stripped of gasoline vapors may still be high in acetylenic hydrocarbons, at times containing ashigh as .20% acetylene.

As an example of operations conducted upon hydrocarbon gases of a more or less saturated type such as natural gas mixtures, a natural gas containing 75% of methane, 15% ethane, 5% fpropane and the balance higher hydrocarbons, may be heated during passage through a 'coil similar to 26 in the drawing to a temperature of l200 F., a pres sure of approximately 300 pounds per square inch being maintained upon the gas during its passage through the coil. The heated and partially converted gases may then be flashed intoI an ultra violet light treating chamber such as chamber 30 in the drawing wherein they are exposed to the light influence under a pressure of about 12 pounds below atmospheric. By this treatment may be produced a yield of 6 gallons of motor fuel jecting the same under the lower pressure to the action of ultra violet light.

2. A process for treating normally incondensible hydrocarbon gases which comprises heating the same under superatmospheric pressure to a temperature of between 1200 F. and 1850 F., and then exposing the thus heated gases under vacuum to the action of ultra violetlight.

3. A process for producing acetyleneand liquid hydrocarbon motor fuel which co'mprises heating the normally incondensible gases produced in' the cracking' of hydrocarbon oils to between 1200 F. and 1850o F. under superatmospheric pressure, then treating the gases while still hot with ultra violet light under vacuum, and separating the vapors thus formed from the gases by con densation.

In testimony whereof I afliX my signature GUSTAV EGfLOFF.` 

